钛微合金化Q390钢的纯净度研究

针对国内某钢厂生产的含Ti微合金钢Q390（采用BOF-LF-RH-CC工艺流程），对LF处理前、LF处理后、RH处理后、中间包环节及连铸坯取样，通过光镜、电镜能谱分析及大样电解等手段研究分析了该钢种的纯净度和夹杂物演变行为。结果表明：该钢种工艺生产过程稳定，生产的钢水纯净度较高，铸坯中大型夹杂物数量为1.4 mg/10 kg，夹杂物以CaO-SiO2-Al2O3复合为主，一些大型夹杂物中复合了较高含量的Ti。另外，对钢中一些典型夹杂物的产生机理进行了阐述。

Study on cleanliness of Ti micro-alloying steel Q390

For the Ti micro-alloying high strength steel Q390 produced in a domestic steel mill with BOF-LF-RH-CC route， the cleanliness and non-metallic inclusions evolution during the smelting and continuous casting are studied. By means of OMS， SEM and EDS， and bulk sample electrolysis， the purity of steel and evolution behavior of inclusions is investigated. The results show that the production process is steady-going， and the cleanliness of Q390 produced by this route is high. The amount of large size inclusions is 1.4 mg/10 kg in the CC slab， moreover， the most non-inclusions are CaO-SiO2-Al2O3 system complex compounds with higher content of titanium appeared in some inclusions. Meanwhile， the mechanism of some typical non-metallic inclusions arisen during metallurgy process is analyzed.